class TestView(View):


    def get(self, request):
        
        firmware_path = firmware_obj.firmware_path

        # 下载文件
        if firmware_path.startswith("/data/"):  # 本地文件
            file_name = os.path.split(firmware_path)[-1]
            data = file_iterator(firmware_path)
        else:  # 文件流
            oss = Oss(**settings.ALI_OSS_CONF["narwal_firmware_private"])
            res = oss.download_stream(firmware_path)
            file_name = firmware_path
            if not res:
                return JsonResponse({'msg': 'system oss error'})
            data = file_iterator_file_object(res)

        response = StreamingHttpResponse(data)
        response['FILE_NAME'] = file_name
        response['Content-Type'] = 'application/octet-stream'
        response['Content-Disposition'] = 'attachment;filename=%s' % file_name
        return response

def file_iterator(file_name, chunk_size=8888):
    with open(file_name, "rb") as f:
        while True:
            c = f.read(chunk_size)
            if c:
                yield c
            else:
                break


def file_iterator_file_object(file_object, chunk_size=8888):
    while True:
        c = file_object.read(chunk_size)
        if c:
            yield c
        else:
            break